- Correspondence to Dr Stuart G Nicholls, Department of Epidemiology and Community Medicine, University of Ottawa, Ottawa, K1H 8M5, Canada;
- Received June 9, 2011
- Revised November 22, 2011
- Accepted November 24, 2011
- First published December 20, 2011.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.